"Rich people spend a lot more money on their own problems, like baldness, than they do to fight malaria," he told Süddeutsche Zeitung. That month, the style-conscious prime minister had "mystified" Italians by suddenly appearing outside a Milan hospital sans much of his transplanted rug, which, in 2004, had given him so much masochistic joy ("I am very happy to have subjected myself to such pain").

But Gates, blessed at 54 with a full head of filamentous biomaterial, seems to have overlooked the palpable link between follicular health and power dynamics. The Guardian's Hadley Freeman has written on the "most unfair state of affairs" that "discriminates against baldies"; Samson's struggles to come to terms with his hair-related self-esteem issues, meanwhile, famously resulted in much unnecessary strife -- his inability to adjust to an unfortunate haircut led to eye surgery at the hands of the Philistines, whose licences to practise in ocular care had not been approved by the General Optical Council.

Hair has recently spiked in value, with a lock that belonged to Napoleon fetching £8,600 at a New Zealand auction. The prestige attached to the former French emperor's hair, however, was no match for that of the singer Elvis Presley, who was allegedly a king. A "wad" of his jet-black hair the size of a cricket ball sold for $115,120 in 2002; a single strand was purchased last year for £1,055.

In North Korea, the dissident potential of long hair raised alarm among the ruling elites in 2005; that year, the government launched a television campaign exhorting men to get "a proper short-back-and-sides". It went on to name and shame transgressors, insisting that: "People who wear others' style of dress and live in others' style will become fools and [the] nation will come to ruin."

Yet the North Korean tactic of clamping down on hair crime is, perhaps, flawed. The leader of Japan's Your Party, Yoshimi Watanabe, has instead taken a more proactive approach, exploiting hair's semiotic value for political gain. Though formerly mocked by colleagues for being the leader of the "new party [of] one person", Watanabe's followers swept this month's House of Councillors election, winning ten seats.

Many, including the Mainichi newspaper, have ascribed Watanabe's recent success to his distinctive "antenna" hairstyle, reportedly based on David Beckham circa 2002. "He had tried various styles with a trial-and-error approach," it said, "including one with bangs and a swept-back style. But his 'Beckham' cut garnered the most support."

On a final note, it's worth noting that the new Australian prime minister Julia Gillard's partner is a former hair product salesman. More on this from John Pilger in the next issue of the New Statesman, out Thursday.

Bertie Carvel's diary: What would the French think about infidelity to Doctor Foster?

According to the adage, the first thing an actor does when he gets a job is to go on holiday. And so, having finished our sold-out run of James Graham’s Ink at the Almeida and with the show (in which I play a young Rupert Murdoch) about to transfer into the West End, I’m packing my bags.

But before I can skip town, I’ve one more professional engagement: the press launch of series two of the BBC drama Doctor Foster, which we finished filming at Christmas. I’ve now seen the final cut of all five episodes, and I’m excited to share it with an audience. There’s no substitute for seeing other people’s reactions at first hand, especially with a show that got people talking so much first time around, and it’s electric to sit in a cinema full of expectant journalists and commentators and feel the room respond. Nothing beats this: to put so much into making a thing and then experience an audience’s unmediated, reflexive reaction. When it goes well, you feel that you’ve shared something, that you’ve all recognised something together about how things are. It’s a unifying feeling. A sort of bond.

Cheating spouses

Handling the interviews has been tricky, when there’s so little one can say without giving the plot away. (The first series began with Suranne Jones’s character Gemma, a GP, suspecting her husband Simon of having an affair.) What’s more, lots of the questions invite moral judgements that I’ve tried my best to avoid; I always think it’s really important not to judge the characters I play from outside, but simply to work out how they feel about themselves, to zero in on their point of view. There’s a sort of moral bloodlust around this show: it’s extraordinary. People seem to want to hear that I’ve been pilloried in the street, or expect me to put distance between myself and my character, to hang him out to dry as a pariah.

While I’m not in the business of defending Simon Foster any more than I’m in the business of attacking him, I am intrigued by this queer mixture of sensationalism and prurience that seems to surface again and again.

Shock horror

Oddly enough, it’s something that comes up in Ink: many people have been surprised to find that, in a story about the re-launch of the Sun newspaper in 1969 as a buccaneering tabloid, it’s the proprietor who considers dropping anchor when the spirit of free enterprise threatens to set his moral compass spinning.

I’ve never given it much thought before, but I suppose that sensationalism relies on a fairly rigid worldview for its oxygen – the SHOCKERS! that scream at us in tabloid headlines are deviations from a conventional idea of the norm. But what’s behind the appetite for this sort of story? Do we tell tales of transgression to reinforce our collective boundaries or to challenge them?

For me there’s a close kinship between good journalism and good drama. I’m reminded of the words of John Galsworthy, who wrote Strife, the play I directed last summer, and who felt that the writer should aim “to set before the public no cut-and-dried codes, but the phenomena of life and character, selected and combined, but not distorted, by the dramatist’s outlook, set down without fear, favour, or prejudice, leaving the public to draw such poor moral as nature may afford”.

So when it comes to promoting the thing we’ve made, I’m faced with a real conundrum: on the one hand I want it to reach a wide audience, and I’m flattered that there’s an appetite to hear about my contribution to the process of making it; but on the other hand I think the really interesting thing about the work is contained in the work itself. I’m always struck, in art galleries, by how much more time people spend reading the notes next to the paintings than looking at the paintings themselves. I’m sure that’s the wrong way around.

Insouciant remake

En route to the airport the next morning I read that Doctor Foster is to be adapted into a new French version. It’s a cliché verging on racism, but I can’t help wondering whether the French will have a different attitude to a story about marital infidelity, and whether the tone of the press coverage will differ. I wonder, too, whether, in the home of Roland Barthes, there is as much space given to artists to talk about what they’ve made – in his 1967 essay, “The Death of the Author”, Barthes wrote that “a text’s unity lies not in its origin but in its destination”.

No stone unturned

Touring the villages of Gigondas, Sablet and Séguret later that evening, I’m struck by the provision of espaces culturels in seemingly every commune, however small. The French certainly give space to the work itself. But I also notice a sign warning of a chat lunatique, so decide to beat a hasty retreat. Arriving at the house where I’m staying, I’ve been told that the key will be under a flowerpot. Lifting each tub in turn, and finally a large flat stone by the door, I find a small scorpion, but no key. I’m writing this at a table less than a yard away so let’s hope there won’t be a sting in this tale.

Ink opens at the Duke of York Theatre, London, on 9 September. More details: almeida.co.uk